Night Patrol Dominoes

Coming back inside after dusk, I marched straight to the bookshelf! Absolute chaos on the lower shelf. Paperback books were leaning around like sloppy statues! Completely unacceptable. I shoved my way behind a row of mystery novels, kicked out my heels, and shoved hard. Thud, thud, thud, smack! Exactly four books tumbled in a flawless domino cascade onto the wooden floor below! Spectacular sound! I stood perched on the edge of the shelf to admire my clean floor landing zone. Four fallen obstacles, zero mess left on my shelf. Mission accomplished!